A spinning device of an open-end rotor spinning machine is known from EP 1 283 288 A2. A thread is spun in an open-end spinning device and delivered to a winding device. For the defined laying of the delivered thread on a bobbin, a thread traversing device driven by a single motor is provided. After a thread break, the thread end that arises from this is wound onto the bobbin. In order to use such thread end for re-attachment with a new thread, it must be sought out on the bobbin. For this purpose, a swivel-mounted suction nozzle that is subject to negative pressure is provided. In the event of a thread breakage, the suction nozzle swivels from a lower position upwards to the bobbin circumference of the bobbin and subjects it to suction. The bobbin is set in a rotational movement, such that, after a certain time, the thread end is captured and extracted with suction by the suction nozzle. Subsequently, additional handling takes place in order to use the thread end for re-attachment. For this purpose, the thread end is delivered by the suction nozzle to other devices. This procedure is time-consuming, since the suction nozzle must be first set in motion and the thread end that is found must be delivered to other handling devices through corresponding movements. In addition, the structural complexity and the installation space required are considerable.
A suction nozzle arranged in a fixed location, which is allocated to a bobbin on a winding machine, is known from EP 0 128 121 A1. Upon a thread breakage or prior to the attachment of the thread of a new delivery bobbin on the thread end of the thread wound on the bobbin, the bobbin is stopped. Subsequently, it is rotated in the direction counter to the winding direction, in order to wind a thread end of the bobbin that is sufficiently long for the attachment process. So that the end that is generally strongly adhering on the bobbin surface can be found and detached, a suction source is turned on and negative pressure is built up in the suction nozzle, which propagates through the mouth up to the bobbin surface. Given the negative pressure, air from the environment is sucked in through the gap between the mouth lips of the nozzle. At that point, the thread end drawn in from the bobbin surface by the negative pressure that is prevailing there is captured, carried away and drawn off by the powerful current in the interior of the nozzle. The disadvantage here is also that the thread end that is found must be removed from the nozzle, prepared for attachment and brought back into the normal thread path. Moreover, during operation, this device is time-consuming and accordingly disadvantageous for the efficiency of the machine.
A winding machine that guides the thread in a thread guide channel between the feed bobbin and the winding device positioned in the unwinding position and completely encloses it is known from EP 2 444 347 A2. After the guiding channel, a suction head that can be swiveled is provided, with which a thread end can be captured on the bobbin and can be clamped between the bobbin and the mouth of the suction head. For the further handling of the thread, it must be delivered back to other handling devices. In the thread guide channel, various thread monitoring devices and thread treatment devices are arranged. Because of the long, stationary thread guiding channel, in the event of clogging caused by the thread, cleaning can be very complex.